A blockbuster asthma drug once heralded as a medical breakthrough is now under fire after new research revealed its potential connection to severe mental health risks, including suicidal thoughts and actions. The drug, montelukast—branded as Singulair and also sold generically—was initially praised for offering asthma sufferers a convenient pill alternative to inhalers. However, mounting evidence suggests the medication may come with far more dangerous side effects than initially disclosed.
When Merck & Co. introduced Singulair in 1998, it was marketed as a near-miracle solution with side effects so minimal they were likened to those of a sugar pill. Millions of prescriptions were written, making it a staple for both adults and children managing asthma and allergies. Yet behind the marketing success lay growing reports of alarming neuropsychiatric side effects, from depression and anxiety to suicidal behaviors.
By 2019, the U.S. Food and Drug Administration (FDA) had recorded thousands of such adverse-event reports, including at least 82 suicides, 31 of which involved individuals under the age of 19. In response, the FDA slapped a “black box” warning—its most severe advisory—on montelukast in 2020, cautioning that the drug could cause serious mental health effects.
At a recent scientific meeting in Austin, Texas, FDA researchers presented preliminary findings revealing that montelukast binds to brain receptors critical for mood, impulse control, cognition, and sleep. This mechanism is eerily similar to that of antipsychotic drugs known to cause psychiatric side effects. Although the FDA has stated that its findings are not yet conclusive, Austrian researchers Julia Marschallinger and Ludwig Aigner argue the data supports years of anecdotal reports from patients and their families.
“It’s definitely doing something that’s concerning,” Marschallinger told *Reuters*, emphasizing the drug’s detectable presence in the brain despite earlier assurances from Merck that such distribution was “minimal.”
The toll of Singulair’s potential side effects is heartbreakingly personal. Robert England, whose 22-year-old son Nick took his life just days after starting montelukast, remembers how his once-healthy and happy son became unrecognizable in a matter of days. “He was completely healthy and had no mental health problems prior to taking the drug,” England said.
England’s story is not unique, as families across the country have reported similar tragedies linked to the medication. Meanwhile, lawsuits have surfaced accusing Merck of downplaying the risks during the drug’s early development and marketing phases.
Despite the backlash, Organon, the company now marketing Singulair following a Merck spinoff, maintains its confidence in the drug’s safety profile. In a statement, the company claimed the product label adequately warns about risks and benefits.
Critics, however, remain skeptical, questioning why it took decades of adverse-event reports and FDA investigations for these risks to come to light.
This case serves as yet another example of the dangers of over-reliance on regulatory agencies and corporate assurances. Families should be empowered to make informed decisions about their healthcare, but that requires transparency from pharmaceutical companies and vigilance from government watchdogs.
For many, the damage caused by montelukast cannot be undone. But the question remains: how many more lives must be upended before accountability and reform become more than just buzzwords?
